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51.
ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids.  相似文献   
52.
A new variety of Monochoria C. Presl from Thailand, M. vaginalis (N. L. Burman)Kunth var.angustifolia G. X. Wang, is described. This variety can be distinguished from the typical one, M. vaginalis var. vaginalis, by having mature leaves narrowly lanceolat  相似文献   
53.
In anesthetized in vivo preparations, responses of two types of extraocular muscle fibers have been studied. The small, multiply innervated slow fibers have been shown to be capable of producing propagated impulses, and thus have been labeled slow multi-innervated twitch fibers. Fast and slow multi-innervated twitch fibers are distinguished by impulse conduction velocities, by ranges of membrane potentials, by amplitudes and frequencies of the miniature end plate potentials, by responses to the intravenous administration of succinylcholine, by the frequency of stimulation required for fused tetanus, and by the velocities of conduction of the nerve fibers innervating each of the muscle fiber types.  相似文献   
54.
Cadmium (Cd) accumulations in a Cd hyper‐accumulator fern, Athyrium yokoscense (Ay), and tobacco, Nicotiana tabacum (Nt), were kinetically analysed using the positron‐emitting tracer imaging system under two medium conditions (basal and no‐nutrient). In Ay, maximumly 50% and 15% of the total Cd accumulated in the distal roots and the shoots under the basal condition, respectively. Interestingly, a portion of the Cd in the distal roots returned to the medium. In comparison with Ay, a little fewer Cd accumulations in the distal roots and clearly higher Cd migration to the shoots were observed in Nt under the basal condition (maximumly 40% and 70% of the total Cd, respectively). The no‐nutrient condition down‐regulated the Cd migration in both species, although the regulation was highly stricter in Ay than in Nt (almost no migration in Ay and around 20% migration in Nt). In addition, the present work enabled to estimate physical and physiological Cd accumulation capacities in the distal roots, and demonstrated condition‐dependent changes especially in Ay. These results clearly suggested occurrences of species‐/condition‐specific regulations in each observed parts. It is probable that integration of these properties govern the specific Cd tolerance/accumulation in Ay and Nt.  相似文献   
55.
This paper provides guidance on the steps, obstacles and mistakes to avoid in the implementation of community mental health care. The document is intended to be of practical use and interest to psychiatrists worldwide regarding the development of community mental health care for adults with mental illness. The main recommendations are presented in relation to: the need for coordinated policies, plans and programmes, the requirement to scale up services for whole populations, the importance of promoting community awareness about mental illness to increase levels of help-seeking, the need to establish effective financial and budgetary provisions to directly support services provided in the community. The paper concludes by setting out a series of lessons learned from the accumulated practice of community mental health care to date worldwide, with a particular focus on the social and governmental measures that are required at the national level, the key steps to take in the organization of the local mental health system, lessons learned by professionals and practitioners, and how to most effectively harness the experience of users, families, and other advocates.  相似文献   
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1. If fungivorous insect diversity is maintained by host specialisation on particular fungi, it should be higher in the tropics than in temperate or boreal regions owing to high macrofungus species diversity. 2. To reveal the community and food web structure of fungivorous insects on bracket fungi, fungivorous insects were collected from 427 fruiting bodies belonging to 22 genera throughout the development and deterioration process in a 3‐ha plot of lowland dipterocarp tropical rain forest on Borneo Island. 3. Eight hundred and twenty‐nine individuals of 82 coleopteran species in 13 families from 111 fruiting bodies of 15 fungal genera were collected. Tenebrionidae and Staphylinidae were most common. Fifty‐three and 19 insect species were observed on Ganoderma and Phellinus, respectively. The numbers of insect species and individuals on a particular fungal genus were positively correlated with the abundance of that fungal genus. 4. Quantitative food web analysis revealed a high degree of specialisation at the whole‐community level. At least 65% of insect individuals were observed on Ganoderma at every stage of development and deterioration. Diverse insects coexist on one dominant fungal genus, Ganoderma, in contrast to our hypothesis. 5. The high abundance of Ganoderma fruiting bodies, which lack obvious defences against insect feeding, probably influences the bracket fungus–insect food web in this tropical rainforest.  相似文献   
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59.
Thermogenic flowers produce heat by intense respiration, and the rates of O2 consumption (?o2) in some species can exceed those of all other tissues of plants and most animals. By exposing intact flowers to a range of O2 pressures (Po2) and measuring ?o2, we demonstrate that the highest respiration rates exceed the capacity of the O2 diffusive pathway and become diffusion limited in atmospheric air. The male florets on the inflorescence of Arum concinnatum have the highest known mass‐specific ?o2 and can be severely diffusion limited. Intact spadices of Japanese skunk cabbage Symplocarpus renifolius are diffusion limited in air only when ?o2 is maximal, but not at lower levels. True flowers of the sacred lotus Nelumbo nucifera and the appendix of Arum concinnatum are never diffusion limited in air. ?o2Po2 curves are evaluated quantitatively with the ‘Regulation Index’, a new tool to measure dependence of ?o2 on ambient Po2, as well as the conventional ‘Critical Po2’. The study also includes measurements of Po2 within thermogenic tissues with O2‐sensitive fibre optics, and reveals that the diffusion pathway is complicated and that O2 can be provided not only from the surface of the tissues but also from the pith of the flower's peduncle.  相似文献   
60.
To test our hypothesis of hybrid formation involving the ‘independent gametophyte’ phenomenon in ferns, we identified the genomic formulae and ploidy level of gametophytes of the Vandenboschia radicans complex at the periphery of a sporophyte population. We identified haploid gametophytes of V. kalamocarpa (one of the two putative parents of V.×stenosiphon) in a hybrid sporophyte population in Japan that lacks fertile non‐hybrid individuals. Furthermore, diploid sporophytes of the species were not found within a 50‐km radius. This finding supports a hypothesis of hybridization involving the ‘independent gametophyte’ phenomenon and provides a new perspective on the geographical distribution of fern hybrids.  相似文献   
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